Congrats on your 625.
There are a number of highly respected revolver 'smiths out there. You suggested you were looking for a competition package, so if your 625 is something you might use at local matches, check out Mike Carmoney. He's a highly respected competitive wheelgunner himself, and between Randy Lee and himself, they seem to do many of the action jobs for competitive wheel gunners. Since the 625 is a very popular gun in competition, he knows them very well. And he's a terrific guy to deal with, reasonable rates, and has a pretty quick turnaround to boot.
I don't have a 625 (it's on my list), but I have a 4" 686 that I had "Carmonized": Rendered DAO, action job, aftermarket sights, chamfered cylinders, smoothed and radiused the trigger. The hammer is really trimmed down, so it shortens the lock time but doesn't whack the frame much and jar the sight picture. It was an accurate revolver before all this work, and although Mike didn't accurize it, it's now a laser. And no reliability issues, even with a 7.5lb trigger pull - it's shot everything I've fed it, including reloads with CCI primers.
All this being said, Mike freely admits he's not a machinist. Guns he's worked on aren't fancy, but are designed to be run hard. Again, though, there are a number of highly respected revolver 'smiths out there that can do the fancy stuff if that's what you're looking for.
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